A Study Comparing the Clinical Benefit of Finerenone Versus a Fixed Dose Combination (FDC) of Extended-Release Torsemide and Spironolactone in Patients With Hypertension and Chronic Kidney Disease (NEPHRON)

A Randomized, Parallel, Two Arm Study Comparing the Net Clinical Benefit of Finerenone Versus a Fixed Dose Combination of Extended-Release Torsemide and Spironolactone in Patients With Hypertension and PRoteinuric ChrOnic KidNey Disease

A study Comparing the Clinical Benefit of Finerenone Versus a Fixed-Dose Combination (FDC) of Extended-Release Torsemide and Spironolactone in Patients with Hypertension and Chronic Kidney Disease.

Study Overview

• Status: Recruiting
• Conditions: Hypertension (HTN)
• Intervention / Treatment: Drug: Combination Product: FDC of spironolactone and ER torsemide; Drug: Combination Product: Stabilized doses of loop diuretic and finerenone

Detailed Description

SAR-ERTSP-01P, A Randomized, Parallel, Two-Arm Study Comparing the Net Clinical Benefit of Finerenone Versus a Fixed-Dose Combination of Extended-Release Torsemide and Spironolactone in Patients with Hypertension and PRoteinuric ChrOnic KidNey Disease (NEPHRON).

• Study Type: Interventional
• Enrollment (Estimated): 30
• Phase: Phase 3

Contacts and Locations

• Study Contact: Name: Sophia Shah, MD; Phone Number: 877-872-7339; Email: sophia.shah@sarfez.com
• Study Contact Backup: Name: Salim Shah, PhD, JD; Phone Number: 877-872-7339; Email: info@sarfez.com

Study Locations

• United States
  • Virginia
    • Vienna, Virginia, United States, 22182
      • Recruiting
      • Sarfez Pharmaceuticals, Inc.
      • Contact: Sophia Shah, MD; Phone Number: 877-872-7339; Email: sophia.shah@sarfez.com
      • Contact: Salim Shah, PhD, JD; Phone Number: 877-872-7339; Email: info@sarfez.com
      • Principal Investigator: Sophia Shah, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Adult male and female patients aged ≥18 years;
2. Are diagnosed with a CKD;
3. Have an eGFR of ≥25 and ≤60 mL/min/1.72 m2;
4. Have an UACR 150-3500 mg/g and Sk 4.5 to 5.0 mmol/L;
5. Have an observed clinic seated systolic blood pressure (SBP) of ≥130 and ≤170 mmHg;
6. Are receiving up to an 80 mg daily dose of furosemide or an equivalent dose of other loop diuretics and and 10 mg daily dose of finerenone for 30 days;
7. Willing and able to comply with all aspects of the protocol and to provide written informed consent from the patient or patient's legally acceptable representative (LAR);
8. Willing to use effective methods of contraception during sexual intercourse with an opposite sex throughout the study.

Exclusion Criteria:

1. Have a diagnosis of type I diabetes mellitus (T1DM);
2. Have uncontrolled hypertension (SBP >170 mmHg);
3. Have primary aldosteronism or endocrine disorders;
4. Have serum potassium >5.0 or <4.5 mmol/L at screening;
5. Unable to continue on 10 mg finerenone or require daily dose of more than 80mg furosemide or equivalent doses of other loop diuretics
6. Have a recent diagnosis of acute kidney injury (≤3 months);
7. Had a cardiovascular event within 3 months prior to screening (e.g., myocardial infarction, stroke, transient ischemic attack, pulmonary embolism, elective coronary artery bypass grafting) or elective percutaneous coronary intervention within 1 month prior to screening;
8. Had hospitalized for worsening heart failure in last 30 days;
9. Have an autosomal dominant or recessive polycystic kidney disease;
10. Have an Addison's disease;
11. Have Hepatic insufficiency classified as Child-Pugh;
12. Have a diagnosis of Lupus nephritis or anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis or any other kidney diseases requiring immunosuppressive therapy;
13. Have a history of organ transplant;
14. Require treatment with potassium-sparing diuretics;
15. Have an active malignancy;
16. Currently taking potassium supplement or potassium binders;
17. Have known hypersensitivity to sulfonamides or related compounds or spironolactone or finerenone;
18. Is pregnant, breastfeeding, or planning to become pregnant during the study;
19. Have participated in another clinical study involving any investigational drug within 30 days prior to Screening;
20. Is considered to be unsuitable for any other reason that may either place the patient at increased risk during participation or interfere with the interpretation of the study outcomes by the Investigator, after reviewing medical and psychiatric history, physical examination, and laboratory evaluation.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Quadruple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Active Comparator: Fixed-dose combination (FDC) of ER Torsemide and Spironolactone tablet; Once daily fixed-dose combination of extended release Torsemide 24 mg and Spironolactone 30 mg	Drug: Combination Product: FDC of spironolactone and ER torsemide; The usual starting torsemide daily dose ranges from 5-10 mg (for hypertension) to 10-20 mg (for heart failure). The initial dose for treatment of heart failure or hypertension is 25 mg daily.
Active Comparator: Active Comparator: Continued on stabilized doses of loop diuretic and finerenone; Oral dose of once daily up to 80 mg furosemide or equivalent doses of other loop diuretics and 10 mg finerenone	Drug: Combination Product: Stabilized doses of loop diuretic and finerenone; Treatment will be up to 80 mg furosemide or equivalent doses of other loop diuretics and 10 mg finerenone

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Comparing Net Clinical Benefit (NBC) of the FDC to finerenone with SBP reduction	SBP ≥10 mmHg reduction from baseline (binary: yes/no).	12 weeks
Comparing Net Clinical Benefit (NBC) of the FDC to finerenone with UACR reduction	NCB is defined as UACR ≥30% reduction from baseline (binary: yes/no).	12 weeks
Comparing Net Clinical Benefit (NBC) of the FDC to finerenone with Serum K⁺ reduction	Serum K⁺ ≤5.0 mmol/L at end of treatment (binary: y/no)	12 weeks

Collaborators and Investigators

• Sponsor: Sarfez Pharmaceuticals, Inc.
• Investigators: Study Director: Chris Wilcox, MD, PhD, Sarfez Pharmaceuticals, Inc.

Study record dates

Study Major Dates

• Study Start (Actual): December 1, 2025
• Primary Completion (Estimated): July 1, 2026
• Study Completion (Estimated): October 1, 2026

Study Registration Dates

• First Submitted: October 29, 2025
• First Submitted That Met QC Criteria: October 29, 2025
• First Posted (Actual): October 31, 2025

Study Record Updates

• Last Update Posted (Actual): March 9, 2026
• Last Update Submitted That Met QC Criteria: March 5, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: spironolactone; extended-release; fixed-dose combination; parallel; finerenone; torsemide; radomized; two arm
• Additional Relevant MeSH Terms: Vascular Diseases; Cardiovascular Diseases; Hypertension; finerenone
• Other Study ID Numbers: SAR-ERTSP-01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No